Option 2: treat the money for buying phototherapy machine as if my sister borrowed it from you. Of course, I can borrow money to pay you back, so my sister can also pay you back slowly in installments every month. That's why the phototherapy machine doesn't belong to you. As for borrowing money, it's up to you whether you want interest or not. But since it is to help my sister, the interest should not be! It's up to you whether to write the IOUs or not. That's the point ...
Because the phototherapy machine belongs to my sister at this time, your role is to help with advertising marketing (distributing leaflets) when my sister sells phototherapy courses in the future, so my sister wants to thank you for your hard work, so as long as the guests come because of the leaflets you distributed, my sister will definitely give you 37 points. Even the package card is 37% of the package card income, that is, you three and your sister seven. ?
However, this 37-point mark is only for guests who get the leaflets you sent and then do phototherapy courses. As for the guests introduced by the guests, you can't share 37 marks with your sister anymore, because my sister has to live, after all, there may be rent problems! ?
Therefore, in this scheme, my sister can also find more relatives and friends to distribute leaflets, which will give them a greater chance (of course, only the guests who get the leaflets they send), and the conditions are the same as yours, so the leaflets must be marked with who sent them.